The invention relates to a one piece snap hinge made of plastic and a container for longitudinally extending diagnostic test carriers.
Snap hinges are known from DE-PS No. 18 13 187 and DE-OS No. 18 08 875. Snap hinges permit a freely movable hinge part to snap into a locking position or an opening position and to remain in either one of these positions. Common plastic snap hinges include a locking member of generally simple and straightforward design, a flexible hinge portion rotatably coupling a cap to the locking member, the cap having a projecting plug portion aligned with an aperture in the locking member to plug the aperture when in a closed position. A tension or spring member may be included proximate to the hinge to provide a spring force for closing the cap.
The two references noted above show hinges by themselves. This is done to show the function of the hinges. When using the hinges on containers or bottles which are injection molded, the hinges together with the container are injection molded in a single operating step. A problem arises in that molding the snap down portion, the hinge, and the receiving or locking piece as a unit limits injection molding to relatively simply constructed containers or, alternately, it requires highly complex injection molds. In addition, due to limits in molding capability, prior art devices have failed to provide a strong spring action for closing the cap or hinge onto the locking member. Design of prior art cap, hinge and locking members has been limited due to integral construction, failing to achieve the potential widespread application of snap hinges.
In addition, prior art snap hinges generally include protruding hinge members when closed, detrimentally affecting the aesthetic appearance of the closure.
Referring now to another embodiment relating to containers for longitudinally extending diagnostic test carriers, these devices are subjected to strict requirements. The term "test strips" as used herein refers to a well-known example of a test carrier. In particular, the reaction layer of these test carriers is very sensitive with respect to moisture. On the other hand, it should be possible to store the test carriers in the package for a plurality of months or even years without impairing their function. Consequently, the packing must be moisture proof over a long period of time. There also must be the possibility to again close the package in a moisture proof manner after the removal of test carriers. The handling of container functions should be relatively simple, in particular when test carriers are involved which should be used immediately by a layman, for example, for self-determination of blood sugar.
In order to meet these requirements, in the past, containers were used wherein the container body consisted of aluminum or glass. They have a circular cross section and they are closed by a circular plug. The moisture tightness is obtained by a flat seal made of rubber in cooperation with a screw locking. More modern embodiments have a plug which is inserted having a sealing face made of plastic adapted to the sealing edge of the removal opening.
These known packages for strip-like test carriers meet the aforementioned technical prerequisites, but the handling of the same leaves much to be desired. For example, diabetics who want to determine the blood sugar level themselves at a regular interval, would like to have a package which could be easier to take along, for example, in the pocket of a jacket, and which permits an easier removal of the test strip.
For other, less demanded products, easy portable flat packages are known which also have easy-to-handle locks. The concept of transferring such structural principals to the packages of test strips has not been followed up, because it was thought it would be useless to fulfill the requirements for test strip packages in this manner. Thus, an essential feature is that the test strip package must be made cost effective, despite its high quality, and must be filled with a high number of test strips.